As one of Firefox’s legions of alpha and beta testers, one of the most frustrating aspects of helping Mozilla develop Firefox is waiting for authors to make their favorite plugins compatible with the new release. This usually does not occur until there is a final release and sometimes an author stops maintaining a plugin and it never happens.
Most plugins have no compatibility issues with new releases and be simply modified to run on Minefield or one of Mozilla’s future releases. There are two simple ways to force install extensions
1) Install Nightly Tester Tools, and then go to Tools\Addons\Override compatibility Issues.
2) Find your plugin’s install file install.rdf This can be easily done on Mac or Windows
– On a OS 10.6, you can use spotlight to find it or look in library/application support/Firefox/Profiles/%profile name%/Extensions
– Open install.rdf with TextEdit and find this line <em:maxVersion>3.1b2</em:maxVersion>
– Change the version to reflect a your release, such as 3.7a1pre for minefield
Warning: Doing this allows you to use the plugin, but robs the developer of taking a first chance to look for problems and fix them. It is possible to cause a fatal errors and to freeze Firefox by using a plugin with untested compatibility. I have never had any problems, but it could happen.